<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style>
		  .box{
		    position: absolute;
		    width: 100px;
		    height: 100px;
		    background: #ccc;
		    left: 0;
		    top: 0;
		  }
		</style>
	</head>
	<body>
	  <div class="box"></div>
	  <script>
	    let boxdom =document.querySelector(".box");
	    function run(){
	      boxdom.style.left=boxdom.offsetLeft+1+"px";
	      requestAnimationFrame(run)
	    }
	    run()
	  </script>
	</body>
</html>
